DEFRAGMENTATION

defragmentation consists of rearranging the divided and spreaded fragments of data and restoring them into fewer fragments or into the whole file.

Defragging your computer can both solve and prevent a number of problems. If you don't regularly defrag your hard drive, your computer may run slowly and/or may take a long time to start up after you turn it on. If a hard drive is too fragmented, your computer may freeze up or not start at all.

HOW TO ACCESS THE THE CONSOLE ON WINDOWS 

Press Windows+R to open Run box. Type “cmd” and then click “OK”

Press Windows+X to open the Power Users menu, and then click “Command Prompt” or “Command Prompt (Admin).”

HOW TO ACCESS THE CONSOLE ON LINUX 

just open the screen icon